While the 5th generation (5G) of mobile networks has landed in the commercial area, the research community is exploring new functionalities for 6th generation (6G) networks, for example non-terrestrial networks (NTNs) via space/air nodes such as Unmanned Aerial Vehicles (UAVs), High Altitute Platforms (HAPs) or satellites. Specifically, satellite-based communication offers new opportunities for future wireless applications, such as providing connectivity to remote or otherwise unconnected areas, complementing terrestrial networks to reduce connection downtime, as well as increasing traffic efficiency in hot spot areas. In this context, an accurate characterization of the NTN channel is the first step towards proper protocol design. Along these lines, this paper provides an ns-3 implementation of the 3rd Generation Partnership Project (3GPP) channel and antenna models for NTN described in Technical Report 38.811. In particular, we extend the ns-3 code base with new modules to implement the attenuation of the signal in air/space due to atmospheric gases and scintillation, and new mobility and fading models to account for the Geocentric Cartesian coordinate system of satellites. Finally, we validate the accuracy of our ns-3 module via simulations against 3GPP calibration results

翻译：尽管第五代（5G）移动网络已进入商业领域，研究界正在探索第六代（6G）网络的新功能，例如通过无人机(UAV)、高空平台(HAP)或卫星等空间/空中节点实现的非地面网络(NTN)。具体而言，基于卫星的通信为未来无线应用提供了新机遇，例如为偏远或原本无法连接的地区提供连接、补充地面网络以减少连接中断时间，以及提高热点区域的流量效率。在此背景下，准确表征NTN信道是合理协议设计的第一步。为此，本文提供了第三代合作伙伴计划(3GPP)技术报告38.811中描述的NTN信道与天线模型在ns-3中的实现。具体而言，我们通过新模块扩展了ns-3代码库，以实现大气气体和闪烁引起的空间/空中信号衰减，并引入新的移动性和衰落模型来考虑卫星的地心直角坐标系。最后，我们通过与3GPP校准结果的仿真对比，验证了所提出的ns-3模块的准确性。